1. Field of the Invention
The present invention relates to an image forming apparatus having a plurality of dot forming elements arranged along an array direction for ejecting droplets therefrom to form dots, which have the same colors as the droplets, on a recording medium.
2. Description of the Related Art
With significant advances in inkjet technology in recent years, it is becoming possible for inkjet printers to produce large color prints of high quality at high speeds. Inkjet printers are widely used particularly in sign and display applications, and are applicable to the printing of POP (Point Of Purchase) posters, wall posters, outdoor advertisements, and billboards, etc., for example. Inkjet printers are capable of producing prints by ejecting droplets of a plurality of ink types, e.g., inks in C (cyan), M (magenta), Y (yellow), and K (black), onto a recording medium to form a number of dots thereon. Various inkjet printers have been proposed to form high-quality images using a plurality of recording heads, i.e., dot forming units, which are capable of ejecting ink droplets in the same colors.
For example, Japanese Laid-Open Patent Publication No. 2004-066468 discloses a recording head having chips as constituent elements thereof, in which color coordinates in a uniform color space are arranged in a sequence closer to the origin of the uniform color space, and axisymmetrically outward from a central line along a direction in which the chips are arranged. More specifically, the recording head is applied to a multipass inkjet printer in which the recording head is reciprocally moved transversely across a recording medium to scan the recording medium to form an image thereon. The recording head is effective to visually minimize image degradations that are caused by ink droplet landing errors.